author(s)
Sucharu Singh, Rajendra Singh and Arun Kumar

abstract
The present investigation was carried out to study the effect of abiotic factors on sucking insect-pests of okra in Western Plain Zone of U.P. in randomized block design with three replications and nine treatments at Horticulture Research Centre of Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut. At weekly intervals, insect-pest population were recorded by randomly selecting five plants per plot. The population of white flies (Bemisia tabaci), jassid (Amrasca biguttula biguttula) and aphid (Aphis gossypii) were recorded on three leaves (top, middle and bottom leaves of the plant). On 22^nd August during 34^th SW (20^th to 26^th August) the aphid, Aphis gossypii (Glover) was first recorded. The major activity period was noted from August to September. The maximum activities of insects were observed during 35^th SW (27^th August to 2^nd September). During this period highest and lowest temperature were 32.6 °C and 21.1 °C respectively, whereas, morning and evening relative humidity were 88.3 and 38.7% respectively. On 29 July during 34^th SW (20^th to 26^th August) the jassid, A. biguttula biguttula was first recorded. Major activity period of insects were August to September. On 22^nd August during 34^th SW (20^th to 26^th August) the whitefly, Bemisia tabaci Genn. Was first recorded.